Good:
-creative and artistic
-love to express themselves using indirect methods, such as writing, music or art, etc. And are often very good at it.
-love to daydream and do it a lot
-will never ever ever ever ever betray you. I don't know if this goes under loyal so...

Bad:
-procrastinate a lot
-tend to go into 'the mood', where you basically feel so sad and hate yourself and the world you live in.

Perhaps I'm the only one, but I have poor work ethic. When I feel like doing something, I'm a total perfectionist and will spend hours refining the slightest detail. When I don't feel like working, I either have to force myself to (which often ends up with sloppy results) or put it off for days to week to months.

The good side: creativity, a deeper nature, caring a lot, etc.
Bad side: Unbearable perfectionism, a penchant for criticism (but easily wounded by it, as well), really vitriolic at times. But hey, maybe that's just me, and not the archetype itself. :p

"Good" :
1) creative
2) appreciate harmony in nature, in groups, in one-to-one relationships
3) appreciate beauty in people (inside first and then external), of nature, of the universe, of ideals, of values
4) seeking their own path through life
5) genuine
6) unconventional
7) spiritual
8 ) loyalty to causes, their values, their families, and friends
9) able to generate many possibilities and solutions when working on a problem or writing something or making decisions
10) caring and showing genuine empathy toward an another being without seeing anything in return
11) committed to anything that they like to do, like to love, like to identify with
12) flexible, adaptable, laid-back (some)
11) intelligent and usually well-read

"Bad"
1) tend to believe that all other people are as good as they are - naive and trusting which after being burned 1 billion times leads into bitterness and complete distrust
2) avoiding conflict for the sake of harmony - or turning other cheek only to explode or implode after they are slapped on that cheek hard and long enough - the target of such reaction (explosion) does not have to always be the cause of the conflict or a person that hurt them in the first place, but somebody that resembles the one that hurt them
3) pay attention on what is said (whether true or not) instead on who said it (e.g. one is being repeatedly told by a uneducated bully that he or she is stupid (an INFP person), but they are not considering why the person who called them stupid is a such a j...k. The bully might feel jealousy of their success and might be feeling inferior due to his/her own insecurities, or are of lower intelligence
4) Being overly critical of oneself and perfectionistic which stems from insecurities that are rooted in how others perceive them (Fe is here too much)
5) Expecting others (and often one selves are not able to) to fit their high values and ideals - throwing a fit or lashing out or taking a control of a project when this is not fulfilled.

"creative, smart, idealist, loner, attracted to sad things, disorganized, avoidant, can be overwhelmed by unpleasant feelings, prone to quitting, prone to feelings of loneliness, ambivalent of the rules, solitary, daydreams about people to maintain a sense of closeness, focus on fantasies, acts without planning, low self confidence, emotionally moody, can feel defective, prone to lateness, likes esoteric things, wounded at the core, feels shame, frequently losing things, prone to sadness, prone to dreaming about a rescuer, disorderly, observer, easily distracted, does not like crowds, can act without thinking, private, can feel uncomfortable around others, familiar with the darkside, hermit, more likely to support marijuana legalization, can sabotage self, likes the rain, sometimes can't control fearful thoughts, prone to crying, prone to regret, attracted to the counter culture, can be submissive, prone to feeling discouraged, frequently second guesses self, not punctual, not always prepared, can feel victimized, prone to confusion, prone to irresponsibility, can be pessimistic

Bolded I find mostly true (negative characteristics usually under stress or during some difficult moments/decisions in life, in difficult environments and around difficult people)

http://www.bestfittype.com/infp.html:
"What’s it like to be you?
I have a very internal focus. I think I look at myself through other people’s eyes, but sometimes I can lose touch with how things work for me. Then I can get introspective, going very deep and staying there, not coming out too quickly or easily. Somehow I find it very difficult to put into words and communicate the things that really matter to me. Most people don’t have the foggiest notion about what goes on with me.

I like harmony and seek consensus and do well with the deep issues. My values and the things that are important to me often feel outside the mainstream in the sense that I feel impinged upon and uncomfortable with so much of what goes on. I’m too private to push my values on to other people, but I am convinced that one ought to be congruent in their own life if they are going to expect congruence from others. In a sense I hold other people to that standard, and I worry about my own incongruities, inconsistencies, and contradictions. Groups can be hard. I can put myself in the group process so rapidly and so completely, and it’s important not to get sucked in. I need to be predictable about what I believe.

I am a global thinker and I like to learn interactively. My thoughts need to be connected with some person or value. On reflection, don’t all thoughts have to be connected to something? I feed new information into other things I’ve read and my thoughts, and I can have a marvelous time just sitting with ideas. And I like to discuss or write things because I seem to have a lot in my head and I’ve got to get it out. I love bringing together different eclectic ideas and seeing what’s similar. I like to have my own ideas, hear others ideas, and have ideas challenged, bantering back and forth. Chitchat has no interest for me. I tend to do a lot of mental rehearsal and play in problem solving, and the fun part is figuring out how to do something. Motivation comes when something has real meaning or value for me, and while I enjoy ideas I don’t like having my values challenged.

For me, asking questions is just a different form of being quiet, a way to explore an inner thought stream or check out of reality and back into my thoughts. Sometimes I chuckle at myself that there is really no sequential way that I work though tasks..."

I love that description... sorry I don't have a concise list. I may try to create one later.

Good:
-Is trusting
-Very creative, imaginitive, and can express themselves in a variety of ways (just not through talking) -_-
-Are global thinkers, have no problem learning a new language and respect other cultures and religions (in my experience anyways)
-Really overall believe in the goodness of mankind

Bad:
-Become very pessimistic and existential when depressed.
-The smallest things can make one depressed.
-Can be too trusting.....
-Can respond badly in stressful situations sometimes. Other times we will be completely calm and cool.
-Have trouble focusing for long periods of time, doing things they're not interested in, and are forgetful and lose things easily

Phil wrote:Perhaps I'm the only one, but I have poor work ethic. When I feel like doing something, I'm a total perfectionist and will spend hours refining the slightest detail. When I don't feel like working, I either have to force myself to (which often ends up with sloppy results) or put it off for days to week to months.

Oh, hello. Are you my long lost twin?
(I have to read a 40 chapter history book in like three days because of this. Aw heck, I'll start it tomorrow).

By this time, it had become obvious to me that the only possible solution to my problem was chocolate.

1) tend to believe that all other people are as good as they are - naive and trusting which after being burned 1 billion times leads into bitterness and complete distrust
2) avoiding conflict for the sake of harmony - or turning other cheek only to explode or implode after they are slapped on that cheek hard and long enough - the target of such reaction (explosion) does not have to always be the cause of the conflict or a person that hurt them in the first place, but somebody that resembles the one that hurt them
3) pay attention on what is said (whether true or not) instead on who said it (e.g. one is being repeatedly told by a uneducated bully that he or she is stupid (an INFP person), but they are not considering why the person who called them stupid is a such a j...k. The bully might feel jealousy of their success and might be feeling inferior due to his/her own insecurities, or are of lower intelligence
4) Being overly critical of oneself and perfectionistic which stems from insecurities that are rooted in how others perceive them (Fe is here too much)
5) Expecting others (and often one selves are not able to) to fit their high values and ideals - throwing a fit or lashing out or taking a control of a project when this is not fulfilled.

1. NO
2. Rarely
3. NO
4. I DON'T KNOW HOW ABOUT THE OTHERS
5. Yah... I have no time for sh*tty ppl.
- Perfect INFP

Bad
Loners, (absolutely necessary and totally understandable, but can take it too far, I have )
Sensitive in a self destructive way, ie holding on to hurt
Can be hard to reach even for the well meaning souls out there.
Intense, at least everyone says I am.